Tyre pressure Suzuki King Quad 300

[SDK777]

Hi everyone, I have a Suzuki King Quad 300. I live in 4.5 acres which is quite rocky with a lot of ups and downs. With the solid rear axle it is a very hard ride and can only be ridden quite slowly. Is 5 psi too low? At that pressure it is a lot more forgiving.

[Mech]

Hi. The manual says recommended operating pressure of 4.4psi for the front and 4.0 for the rear, and a maximum operating pressure of 5.1psi.

I suppose you have tried adjusting the suspension' spring pressure ?

[Ajmboy]

Those are nice quads with the shifters (I think this has them) and low center of gravity, but not the most comfortable.

Topic moved to Suzuki ATV Forum. 😁

[alexwv1863]

I put more in mine. My Arctic Cat holds up to 30psi and I use 20. Im not sure about your max psi, but I would put more in it. Id try 10psi but def go by the max rating on your tires. I can't tell you to do something I would do and have it be a wrong judgement call, but in rocky terrain, your tires need to have more psi in them. You'll noticed a huge change in steering and control too. 

[davefrombc]

I  run 5 psi in the tires on my old '91 Honda Fourtrax 300FW. The tires are rated for 7psi max.  It is also a solid axle rear ,  full time 4x4 and as such has the turning circle of a pickup truck and  a harsher ride than the newer independent suspension rigs with selectable  2- 4WD. Simple , dead reliable old technology but much easier to  maintain like most of the old Hondas and Suzukis.

 5 psi  is fine in your quad, and  you could easily run  them  at the recommended 4.4 psi. The low pressure gives a  little less harsh ride and  better grip  in rough terrain.

Hard core 4x4 offroaders drop their vehicle tires from  highway 30 -50  psi pressures  down  to as low as 10 - 15psi.  Some with bead lock rims drop pressures  into the single digits for rock crawling.  Softer tires give better grip and ride ,  harder tires give better fuel  mileage and handling on the highway.

[SDK777]

On 7/6/2022 at 4:45 AM, Mech said:

Hi. The manual says recommended operating pressure of 4.4psi for the front and 4.0 for the rear, and a maximum operating pressure of 5.1psi.

I suppose you have tried adjusting the suspension' spring pressure ?

Thanks for the reply, didn’t know I could adjust the suspension. How do I go about it?

[Mech]

If you look at each shock you'll find at one end of the spring, there's a sleeve that can be rotated. As the sleeve's rotated it moves endways to put more or less pressure on the spring.

They are made to be moved with a "C" spanner, which most people don't have, but can be rotated with a pipe wrench if care is taken. They don't get moved often and so the sleeve tends to be jammed full between the sleeve and the shock with dirt. It needs cleaning a bit, and lubing with some oil, before trying to turn it with a pipe wrench. Find the adjuster and clean it as best you can, give it a spray with lube, and then try turning the sleeve a little in either direction, then the other direction. Work it back and forwards a little at a time until it rotates, and slides, nicely. Then back it off till there.s minimum preload on the spring.

If you don't clean it nicely, and lube it, there's a danger the pipe wrench will crush the sleeve against the shock doing damage. Clean  it, lube it, and work it gently till it turns and slides..